UPCOMING ENGINE EMISSION DESIGNS AND ENGINE OIL TRENDS

Lawrence Ludwig, Jr., CLS,OMA,CMFS

Topics

• Emissions Strategies 2010 – up– On-Highway

• OEM Strategies and Types of Devices• Engine Oil Effects

– Off -Highway– Off -Highway• Tier 3 and 4 Engines and OEM Strategies• Engine Oil Effects

– Effects of Biodiesel on Engine Oils

Regulations• The Clean Air Act of 1990 mandated a reduction

emissions for both gasoline and diesel engines.

• Since 1997 the EPA has adopted stringent emission standards for on-highway diesel engines in order to reduce Nitrous Oxide (NO ) engines in order to reduce Nitrous Oxide (NO X) and Particulate Emissions(PM).

• In 2008 off-highway diesel engines began to be more severely regulated for NO X and PM Emissions.

Emission Standards for NO X and Particulates - On Highway Diesel

19881990

19914

6

8

10

12

x,g/

BH

P-H

r

10.7

6.05.0

5.04.0

2.0

1.2 19911994

19982000

2002

20100.6

0.250.1

0

2

4

NO

x

.2

..0101

2007

1.2

Year 2006 2007 2008 2009 2010 2011 2012

On-Road

500 – 15 ppm

(Oct 15)

15 ppm 15 ppm 15 ppm 15 ppm 15 ppm 15 ppm

DIESEL FUEL SULFUR TIME TABLE

(Oct 15)

OffRoad

5000 Max

5000 –500 Max(June)

500Max

500Max

500 – 15 Max

(June)

15 Max 15 MaxMarine Locomotive(June)

On-Highway

Emission Strategies & DevicesEmission Strategies & Devices

2010 Technology Strategies – On Highway• Exhaust Gas Recirculation (EGR) ( increased

amounts)• Closed Crankcase Ventilation (CCV)• Exhaust after-treatment

– Diesel Oxidation Catalysts (DOC) (up -stream of – Diesel Oxidation Catalysts (DOC) (up -stream of DPF)

– Diesel Particulate Filters (DPF)– NOX Absorbers (Navistar)– Selective Catalytic Reduction (SCR)

• On-Board Diagnostics.

EGR• Used since 2002 to control NO X.

• Cycles up to 35% of cooled engine exhaust back into the engine air intake.

• A Variable Geometry Turbocharger balances the fresh air/EGR ratio.

• Dilutes the oxygen content of the intake air in the combustion chamber resulting lower peak combustion temperatures.

Closed Crankcase Ventilation (CCV)• CCV was first used to meet the 2007 emissions

requirements .• Removes harmful vapors generated in the

crankcase.• Vapors are discharged into the engine’s intake

system,(usually via the intake manifold), where system,(usually via the intake manifold), where they are burned as part of the combustion process.

• Recovers the evaporated oil and carries it through the exhaust stream.

Exhaust After-treatment

• All OEMs will use either a combination of DOC and DPF or NO X Absorbers and DPF to meet 2010 emissions requirements.

• With the exception of Navistar the OEMs will use • With the exception of Navistar the OEMs will use Selectively Catalytic Reduction (SCR).– Will use Massive Exhaust Gas Recirculation and

emission credits.• Up to 50% of cooled exhaust gas recirculated.• Advanced fuel injection system that operate at 35,0 00 psi.

What Is A Diesel Particulate Filter?• DPFs are aftertreatment

devices used to remove particulate matter from diesel exhaust.

• DPFs physically capture particulates in the diesel

• DPFs physically capture particulates in the diesel exhaust and prevent their discharge from the exhaust pipe. Collected particulates, such as soot are removed from the filter by burning them off at elevated temperatures.

Diesel Oxidation Catalysts (DOC)• DOCs are used to remove

organic particulates (which come from unburned fuel and the engine oil), hydrocarbons and carbon monoxide from diesel exhaust.from diesel exhaust.

• DOCs use catalysts such as platinum or palladium to promote oxidation of organic particulates, hydrocarbons and carbon monoxide, thereby converting them to carbon dioxide and water.

DOCs catalytically convert organic particulates, hydrocarbons, and CO in diesel exhaust to CO2 and water

Continuously Regenerating Traps (CRT)

• CRTs combines a DOC upstream of a particulate filter.

• DOC coverts NO X to nitrogen dioxide (NO 2 ) before the exhaust enters the DPF.the DPF.

• NO2 lowers the temperature required to oxidize/burn off the particulates.

• Allows the CRT to continuously clear itself of trapped particles.

NOX Absorbers

• Technologies include Lean NO X Traps (LNT), Lean NOX Catalysts (LNC) and DeNO XCatalysts.

• Used to remove or convert NO X into a harmless • Used to remove or convert NO X into a harmless gas.

Lean NOX Catalysts (LNC)

• LNC is also known as DeNO X catalysts.• Uses noble metal catalysts of platinum,

palladium or a mixture in the presence of hydrocarbons to reduce nitrogen oxides into harmless nitrogen gas.

• Can be passive or active.• Can be passive or active.• Passive LNC uses hydrocarbons from the

exhaust stream.• Active LNC requires enrichment of the exhaust

stream by the addition of fuel being injected into the exhaust stream.

Lean NOX Traps (LNT) • LNT are also known as NO X absorbers or NO X

Storage Reduction Catalysts (NSRC).• Removes nitrogen oxides from emissions in two

stages.• During the first stage precious metal catalysts • During the first stage precious metal catalysts

convert nitrous oxides to nitrogen dioxide and store the nitrogen dioxide in an alkaline earth oxide as a nitrate salt.

• The stored nitrogen oxides are released by creating a temporary rich exhaust condition and then catalytically reduced to nitrogen gas using unburned fuel as the reducing agent.

Selectively Catalytic Reduction (SCR)• Removes NO X by injecting a

finely atomized Diesel Exhaust Fluid (DEF) from a storage tank into the exhaust stream before it enters a catalyst system.

• The DEF is composed of a 32.5% urea and water solution.32.5% urea and water solution.

• In the presence of the SCR catalyst the exhaust and the DEF react to convert NO X into nitrogen and water vapor.

• Any remaining ammonia that may be present is removed by an oxidation catalyst.

Selectively Catalytic Reduction (SCR)• Technology is used extensively in Europe.

– DEF marketed as AdBlue.

• DEF tank must be refilled periodically– Consumed at rate of 2-4 gallons for every 100gals

of diesel fuel the vehicle consumes.• Truck that does 120,000 miles/yr uses 20,000 gallon s of • Truck that does 120,000 miles/yr uses 20,000 gallon s of

fuel/yr at 6 mpg would use 400 gallons of DEF (2% r ate)

– DEF tank size is scaled to ~2.5 times the size of the fuel tank capacity.

• Assuming 3% dosing tank capacity equals 3 gals X 2. 5 = 7.5 gals.

• Tank sizes will generally range from 5 to 30 gallon s for medium duty vehicles.

Selectively Catalytic Reduction (SCR)

• SCR will offer 3 to 5% fuel economy benefits over existing technologies.– More efficient engine operation.– Allows for reduced EGR flow rates and

better fuel use.better fuel use.• Slight improvement in performance with higher

power density.

Urea Issues

• Corrosive to aluminum. Must be stored in stainless steel or polyethylene tanks.

• Freezes at about 11 °F.• Above 86 °F begins to separate and

evaporate.evaporate.• DEF injectors have to be self purging to

prevent the build-up of crystallized urea.• Storage tanks will add vehicle weight.

Urea Issues• Possible extra maintenance.

– Filter changes (changes at 150,000 miles)

• Cost for Urea.

• Vehicles equipped with sensors.– If bad urea solution or no urea engine will de-rate

and vehicle will lose power.– Vehicle speed limited at 15 mph.– Shut down and no re-start without re-fill.

Engine oil effects• MEGR can introduce more soot and increase

engine operating temperatures.• Use of SCR and EGR will decrease levels of

soot.• Retrofits containing DPF mandated by CARB

and other governmental agencies will require the use of low SAPs engine oils.the use of low SAPs engine oils.– All vehicles that operate in CA must be upgraded

by 2014.• API CJ-4 will meet the demands of 2010

engines.– More robust additive technology.

• Provides increased soot and corrosion protection.– Low SAPs.

Off-Highway

Emission Strategies & DevicesEmission Strategies & Devices

Off-Highway emissions• Off-highway engines from 50 to 750 HP (37 to

560 kW) have been regulated for NO X and Particulate Matter emissions.– Emissions reductions have been slowly phased in

since 1996 according to horsepower ratings by Tiers.

• Tier 1 spanned 1996 through 1999• Tier 1 spanned 1996 through 1999• Tier 2 spanned 2001 through 2004• Tire 3 spanned 2006 through 2008• Interim Tier spans 2008 through 2012• Final Tier 4 spans 2012 through 2015

– By 2015 NOX emissions will be reduced by more than 90% and Particulate Matter by more than 95%.

Emission Standards – Off Highway

Off-Highway emissions• Current off-road emission regulations cover

Tier 3 and Tier 4 Interim engines.• Tier 3 took effect in 2006, while Tier 4 Interim

takes effect in January, 2011 for engines above 173HP (129kw)

• To meet Tier 3 the following emission • To meet Tier 3 the following emission technologies are being used:– ACERT (Cat) or Cooled EGR– Variable Geometry Turbocharging– Common Rail Advanced Fuel Injection

• Electronically controlled unit injectors• High injection pressures – up to 35,000 psi

Off-Highway emissions – Interim Tier 4 • To meet Tier 4 Interim

emissions the following technologies will be used by the OEMs:– Current Tier 3 strategies

but EGR rates will increase.increase.

– Closed Crankcase Ventilation

– DOC and DPF with either active or passive regeneration.

• DPF needs to be cleaned periodically

Off-Highway emissions – Tier 4 Final• Tier 4 Final emission begin to become

implemented in 2012 and fully take effect in January of 2015.

• To meet Tier 4 final emissions off -highway • To meet Tier 4 final emissions off -highway OEMs will utilize either MEGR, NO Xabsorbers or SCR.

Off-Highway engine oil effects• Currently most off-highway OEMs

recommend the use of CI-4 or CI-4+ engine oils.

• Introduction of Tier 4 Interim engines into fleets will require the use of CJ-4 quality engine oils.

• In California any person, business or • In California any person, business or government agency that owns or operates off-road diesel equipment of 25 or more HP must use best available technology such as DPF to reduce emissions.– Construction, mining, industrial, airport ground su pport.– If DPF are used instead of repowers or engine repla cements

the use of CJ-4 quality engine oils will be require d.

Effects of Biodiesel on Engine OilsEffects of Biodiesel on Engine Oils

OEM position on biodiesel• Most OEMs and fuel injector equipment

manufacturers approve the use of up to B5.• Some OEMs such as Cummins and John

Deere allow up to B20.• John Deere factory fills with B2.

• Requires that the B100 used to blend biodiesel blends meet:biodiesel blends meet:• ASTM D-6751-08• EN 14214 (EU specification)• Produced by a BQ-9000 Accredited Producer

• Certification by National Biodiesel Board

• Finished fuel blends between B6 and B20 should also meet ASTM D-7467-08 Specification for Diesel Fuel, Biodiesel Blend B6 to B20.

Biodiesel & engine oil - problems

• Increased potential for fuel dilution.

• Effects due to biodiesel oxidation stability.

• Materials compatibility with DPF’s.• Materials compatibility with DPF’s.

• Wear and Corrosion.

Fuel Dilution• Rate of fuel dilution is expected to be higher.

• More pronounced in engines that use common rail injection and HUEI type fuel injection systems.

• Biodiesel has higher viscosity, density and surface tension.

• Sticks to the cylinder walls and forms large droplets.droplets.• Gets scraped down into the oil sump.

• Accumulates in the oil sump due to its lower volatility and narrower boiling range.• Progressively builds up over time.

• Older diesel engines especially prone.• Clearances between piston rings and cylinders not

as small.

Fuel Dilution• Excess fuel dilution causes:

• Reduction in engine oil viscosity.• Increased wear.• Tie up of additive systems due to complex chemical

reactions, especially if the biodiesel is oxidized .

• Increased water contamination of the engine oil.

• 1% fuel dilution can introduce 10ppm of water.

• Oil drains may have to be cut in half.

Effects due to biodiesel oxidation stability• Unburnt biodiesel entering the oil sump may

become oxidized thus promoting lubricant degradation.

• Oxidation by products present in biodiesel can cause:cause:• Fuel filter plugging• Fuel pump failure.• Injector deposits.• Fuel system corrosion.• Engine bearing corrosion.• Piston deposits and stuck rings.

• Increase quantity of soot and blow-by gases.

Materials compatibility with DPF• Biodiesel may assist DPF regeneration due

to its ability to produce less soot or amore combustible type of soot.

• However, if the biodiesel contains high levels of calcium, magnesium, sodium and potassium compounds these can contribute potassium compounds these can contribute to the build up of metallic ash in the DPFs.• Blocked filters leading to increased backpressure.• Increased fuel consumption and loss of power• Reduced DPF efficiency.• Increased emissions.• Increased service maintenance intervals for

cleaning of DPF filters.

Wear and Corrosion• Biodiesel oxidation byproducts and any free

fatty acids that are present are known to be aggressive towards lead and copper used in bearings.• Evidence of such corrosion is mixed.

• Increased water contamination can promote • Increased water contamination can promote increased wear and corrosion.

• High levels of fuel dilution can lead to increased wear due to a reduction in viscosity.• Usually happens at fuel dilutions levels of 5% or

greater.

Biodiesel OEM recommendationsCase Construction – B5 to B20 approved. Must meet AS TM D-6751

Case-IH – B5 approved for use in 90% of models. Must meet ASTM D-6751

Caterpillar – Up to B20. Must meet ASTM D-6751. Refe r to SEBU 6250-15, SEBU 6385-07 and SEBU 6251-10 for further recommend ations.

Cummins – Up to B20 approved for use 2002 and later models. Must meet ASTM D-6751.

Detroit Diesel – Authorizes the use of B5 only. Must meet ASTM D-6751 and sourced from a BQ-9000 accredited producer.

Fiat Power-Train – B20 approved for all fuel systems except common rail.

International/Navistar – Unconditionally warrants bl ends up to B5 meeting ASTM D6751 and ASTM D-975. Use of B6 to B20 blends is at the discretion of the operator and will not void warranty.

Isuzu – Neither approves or prohibits using biodiesel . Recommends only using up to B5. Must meet ASTM D-6751. Will not war ranty any failure from the use of biodiesel fuel.

Biodiesel OEM recommendations

JCB – From January 2008 all JCB Dieselmax engines ha ve been approved for the use of B20. Must meet ASTM D-6751.

John Deere – Places B2 factory fill in all of its di esel equipment. B5 preferred. Up to B20 in petroleum diesel can be used in John D eere engines through Tier 3/Stage 3a models including all non-emission c ertified engines. Must meet ASTM D-6751.

Kubota – All Kubota engines can run up to a B5 blend . Must meet ASTM D-6751 and be bought from a BQ -9000 supplier.6751 and be bought from a BQ -9000 supplier.

MTU Detroit Diesel – B5 approved for all engines. Mu st meet ASTM D-6751.

Mack – B5 made from Soy methyl ester only. The biodi esel supplied must be supplied by a BQ-9000 supplier.

Mercedes Benz – Approves use of B5 in all common rail injection diesel CDI engines including Bluetec engines. Must meet ASTM D -6751.

Perkins – Use of B20 approved for its 400D and 1100 series engines. Must meet ASTM D-6751.

Biodiesel OEM recommendations

Volkswagen – B5 is approved for use in all TDI diese l vehicles. Biodiesel blend must meet ASTM D-6751 and ASTM D-975.

Volvo – Up to B5 is approved for use. Must meet ASTM D-6751.6751.